Tuning molecular emission of organic emitters from fluorescence to phosphorescence through push-pull electronic effects

• DOI: 10.1038/s41467-020-16412-4
• Publication Date: 2020-05-26T10:02:38Z
• Authors: Hai-Tao Feng; Jiajie Zeng; Ping-An Yin; Xue-Dong Wang; Qian Peng; Zujin Zhao; Jacky W. Y. Lam; Ben Zhong Tang
• Keywords: Intersystem crossing; Carbazole

Abstract Organic emitters with persistent phosphorescence have shown potential application in optoelectronic devices. However, rational design and tuning are still challenging. Here, a series of metal-free luminophores without heavy atoms carbonyl groups from commercial/lab-synthesized carbazole benzene were synthesized to realize tunable molecular emission fluorescence by simply substituent variation. All the molecules emit blue both solution solid state. Upon removal excitation source, fluorinated show obvious phosphorescence. The lab-synthesized based exhibit huge lifetime difference commercially purchased ones due existence isomer latter samples. small energy gap between singlet triplet state low reorganization help enhance intersystem crossing contribute more competitive radiative process ground Blue white organic light-emitting devices fabricated using luminophore as emitting layer.